Bucket for rotary pumps



Sept, 18, 1928. n 1,685,003

' w. w. McELRATH BUCKET FOR ROTARY PUMPS Filed Nov. 25, 1924 2 SheetsSheet -1 Sept. 18, 1928. k 1, 85,003

W. W. MCELRATH 1 BUCKET FOR ROTARY PUMPS Filed Nov. 25, 1924 Z Sheets-Sheet 2 33 13 a Wi 1&2

7 ate high vacuum in rotary pumps and'dis- Patented Fvept. 18, 19253.

I lessees.

FFMEEI.

BUCKET roe BOTABY PUMP-S.

Application fil d November 195%. Serial No. 752,257.

to bucket umpa and The present n construction as applied to rot the like. a r r The primary object of any invention to :provide a bucket construction adapted to crecharge the fluid handled therein with the least possible etl'or't.

Another object of my invention is to provide an iniiproved bucket construction tor rotary pumps which will permit hip h performance over a wide range of operation.

A further object of my invention is to provide a bucket construction for rotary pumps which will tend to follow the contour of the casing reactionary of the fluid while in operation.

A still further object at my invention is to provide a bucket construction for rotary pumps adapted to follow the casino; reactionary of the fluid impact. and discl'iare e said fluid from the bucket by centrifugal torce duringthe cycle 01. operation. I

A much sought object of my invention is to provide a bucket construction for rotary pumps adapted to improve the volumetric etliciency thereof during; operation.

The above and other objects in view, I shall in the following; specification briu out more complete details, and in which.

Fig. 1 represents an end elevated view of the conventional rotary pump with the head removed. and wherein is shown buckets of my construction.

Fig. 2 represents a cross-sectional view of Fig. 1 taken on line 1-1 showing the relation of easing, rotating element, and intake opening; as well as discharge.

3 represents a plan bottom view or" one of the buckets showing openinojs and blade contour. i

Fig. 4. represents cross-sectional projected View or 3 taken on line lllllll.

Referring more particularly tothe draw.- ggs. and i n which case like numerals are used to designate like parts t roughout the specification. and first in which Fig. 1 is shown to be a conventional lcsig'n of r tary pump mounted on a base, the casing); oi which is designated by numeral 1. In this is mounted a rotating element 2 on shaft 3 and secured thereto by a key 4. The periphcry of saic. rotating element 2 has disposed at intervals buckets 555--e5 shown so arran.

{ ed that they are adapted to swing out against the casing during rotation of the shaft 3. In the casing 1 is formed-an inlet opening designated by numeral 10 and dia metrically opposite is a discharge openi deslgnatcd by numeral 1 1.

are more clearly shown in 2.

The buckets. 5555 as shown have opening); 6 which is adapt cl :to' xreceive the (fluid entering the pump intake 10 andin the constructionet the bucket is formed another jopenin-g 8 separated. trom opening 6 by.

interposed blade 7 This construction is best shown by referring more particularly to Figs. 3 and 4. It is clearly noted that the blade 7 extends vertically and forwardly so to form what might be called a leading blade, while at the rear of the bucket is the following blade designated by numeral 9. The leading blade 7 is shown to be of a curvature such as would cause the following blade 9 to swing outwardly against the casing 1 when being rotated in a fluid such as oils, gasolines, varnishes, water, and other liquids. This reaction is caused by the impact of the liquid as is known to the art.

lit is also desirable to discharge the fluid troin the buckets with as little effort as possible. this is done by allowing the entrapped fluid to be discharged, through opening 8 and if the pump is operating at high speed the fluid will pass out this opening by centrifugal force as is known characteristically of this design of centrifugal pumps.

In considering the operation of the conventional design of rotary pump with my invention as disclosed herein may say that the pump as shown in Fig. 1 is adapted to rotate counterclockwise the bucket 5 passing over inlet opening 10 exhaust the air partially therefrom until sufficient suction is established. todraw the fluid intothe casmg 1 at this point. The fluid coming first into contact with the leading" blade 7 causes a bucket reaction which forces tollowim blade 9 against the casing l tightly enough to insure high vacuum the fluid thus entrapped revolves with the rotating element 2 until it reaches the discharge opening 11 where it is discharged by the difference of relative displacement. Should the pump be operating at speed the :[iuid will pass out of openv 8 in the bucket due to relative shape and them very ineiiicient at low speeds. In my design of bucket construction I find quite a difierence as the fluid impinging on the leading blade 7 aids considerably at low speeds,

various changes; and operating conditions may be employed. and limitation is only made by the spirit of the appended claim.

a What I claim and desire to secure by Letters Patent, is: p r

In a rotary pump, a stationary casing, a rotatable member mounted in the casing and having peripheral pockets therein opening toward the wall of the casing, and a bucket v hinged at one side in each of said pockets,

each of said buckets comprising a pair of side walls provided intermediate their ends with a curved loading blade extending generallyin the direction toward the center of the rotar'y member and having between said side walls and at the outer ends thereof a follower blade spaced from the loading blade and having its inner surface curved in divergent relation to the curvature of the loading blade, said loading blade providing an intake opening at itsinner side and'an outer opening between the loading and following blades, said following blade adapted to receive impactof fluid in the outer opening and adapted for contact with the peripheral wall of the casing. In testimony whereof I afli my signature.

WILLIAM MGELRATH. 

